In general, automotive drivelines transmit torque from an engine and eventually to a set of wheels. Automotive drivelines, such as all-wheel drive (AWD) drivelines, sometimes include power transfer units (PTUs), final drive units (FDUs), rear drive modules (RDMs), electronic differential lockers (EDLs), disconnecting differentials and other types of differentials, or a combination of these components to transmit the torque. The exact components in a particular automotive driveline often depends on the architecture of the overall driveline and on the arrangement of the accompanying engine and transmission.
Furthermore, the PTUs, FDUs, RDMs, EDLs, and differentials can be equipped with disconnect and re-connect capabilities in which disconnected components are no longer driven to transmit torque between them. The capabilities preclude driven torque in regions of the automotive drivelines not needing torque at a particular time. For instance, on-demand AWD drivelines do not always transmit torque among all of its shafts at all times. Disconnect and re-connect capabilities have been shown to enhance fuel efficiency, reduce emissions, and provide yet additional performance improvements.